Saturday, 26 July 2008

I just got some recommendations from an algorithm that were so good that it was creepy. (One of the recommendations was this video.)

It made me realize how such recommendations can be a nice shortcut for a machine into someones heart. (Although it only takes a few wrong recommendations to be kicked out again.)

I wonder if in the near future I'll have gotten used to the idea that an algorithm attached to my attention profile data will know me better than any human being could (and I'm not just talking about music).

Friday, 25 July 2008

I guess this post is a bit off topic. But I’d argue that Last.fm is one of the main MIR related web sites out there, and I found the launch of the new site very exciting.

Here’s a link to the main announcement on our blog (with over 2000 immediate responses from users, most of them are negative). The blog post includes links to the forums where the feedback continued after the comments needed to be closed.

Here’s a Last.fm group with over 11,000 users asking to bring back the old design. An interesting read are also the forums of that group. Some user's have even worked on ways (e.g. using greasemonkey) to bring back the old look and feel.

The negative feedback was being voiced in many different places. Including, for example, in the comment section of an article by the Times Online which focused on how the changes related to advertising.

(Btw, there’s also been a lot of positive feedback, too. For example, there are some positive comments in this digg article.)

When I joined Last.fm over a year ago there were like a million things I thought that could be improved on the site. I was bugging those in charge of the web page design on a daily basis. However, they were already aware of almost everything I was pointing out, and explained that there will be a major redesign coming, and that things will be fixed then. As time went by I started to appreciate the complications of making changes to the old site. It was a site that had grown very quickly in many different directions that weren’t fitting together perfectly anymore.

So more than a year ago my colleagues had started making plans on how they would design the perfect Last.fm if they could start from scratch. I’d also like to mention that almost all of my colleagues are hardcore Last.fm users (and have lots of friends who are Last.fm users, and spend time talking to their moms (or other less technology savvy users) about what difficulties they might have using Last.fm). I think it’s fair to say that most of my colleagues have an excellent understanding of the various issues related to the user experience.

However, at the same time the old site was still in full development. A lot of new features were being launched, integrated, bugs fixed, etc. Maintaining the old site was a full time job for a small (but quickly expanding) team, and my colleagues were spending any free minute they had on completely redesigning Last.fm. I’d also like to add that when they talked about change, it wasn’t simply the design, navigation, and structure that were being considered. A lot of changes involved some serious backend changes and new features. It really was all about making the dream of a perfect Last.fm come true.

Btw, here's an interesting podcast where Hasso Plattner (founder of SAP) talks (among many other things) about the challenges of developing the next version of a product while maintaining the previous version. I'm pretty proud of how my colleagues have mastered this challenge.

When the site went live everyone knew that there was still plenty of room for improvements, but at the same time it was clear that the benefits would largely outweigh the remaining issues. And we also knew that even if the new site were absolutely perfect from the start (which it obviously wasn't), it wouldn't be easy for those who were able to use the old site blindfolded. This included myself: there were several moments of serious frustration where I knew what I wanted to do on the old site, but couldn’t instantly figure out how to do it on the new one. (Btw, continuing to maintain two sites was not really an option.)

Despite all the negative feedback we received (and despite all the effort my colleagues are currently putting into fixing issues the Last.fm community has pointed out), there are already several indicators that the new site might be an even bigger success than we would have hoped for, and most of all it has paved the way for a lot more to come. It’s never been more fun to work at Last.fm! Btw, check out the jobs at Last.fm :-)

Monday, 21 July 2008

The last two weeks I was camping north of London. Because I didn't want to drag a whole library with me I decided to take along only one book on statistics. From the books next to my bed I selected the lightest one which is Schaum's Outline: Probability and Statistics. And it was one of the best packing decisions I made.

It all started in one of my favorite book stores in London where I almost ignored the book in the first place. The book stuck out in the shelf of statistics books because of it's height and because of it's ugly front cover design. The pages felt like those of a telephone book. My expectations were as low as it's price tag (which was £12) and I ignored it. However, the shop only offered a very limited selection of books on statistics. So eventually I turned back to it out of curiosity wondering how bad a book on statistics could be. And then I stumbled upon one of the many interesting problems in the book and tried to solve it, and then I found the next interesting problem, and decided to move to the attached cafe. By the time the store was about to close I didn't want to part with the book. (One example of the fun problems in the book is: given 6 randomly sampled observations from a continuous population what is the probability that the last 2 are higher than the first four? (One way to solve it is to use calculus another way is to use combinatorics.))

The book does not only feature the ugliest front cover of any of the books I ever owned, it also contains many typos. And every time I tried to use the index it seemed to point me to random pages. For example, one typo can be found in the introduction to the multinomial distribution where they forgot an important exclamation mark. I don't understand how they manged to include so many errors in this second edition. In fact sometimes I wondered if errors were included to keep the reader alert. However, none of the errors I found were hard to identify as such. (In the case of the multinomial distribution formula there is an example just a few lines below the typo which uses the correct formula.)

Overall the book is amazing. I had a hard time choosing between packing up my tent in the rain or waiting for the rain to stop while reading a few more pages and drinking some hot tea (btw, I also highly recommend Trangia stoves).

The book is definitely suitable for people (like me) who work with probabilities and statistics on a daily basis but feel like they lack a solid foundation. It helps if you've had a basic course on statistics a long time ago and just want to refresh your knowledge. However, I think it is also largely and easily accessible to anyone who has not had any courses on statistics (although some understanding of calculus will help a lot).

The best part of the book is that it features lots of practical problems that help understand the theoretical concepts. The book is also structured in a way that makes it very easy to spend 30 minutes or less at a time with it. The topics covered include nonparametric tests, curve fitting, regression, and hypothesis testing.

Tuesday, 1 July 2008

Yesterday and today I had the pleasure to spend some time with Masataka Goto talking about how MIR technologies are changing how we create and enjoy music, and in particular what Masataka calls active music listening. It was also great to get some updates on what's happing on the other end of the world.

One thing I found particularly interesting is the VocaListener project which Tomoyasu Nakano (who recently finished his PhD) and Masataka Goto are working on. VocaListener is based on Vocaloid 2 and synthesizes a singing voice that is very hard to discriminate from a real singer.

Here is a video featuring the synthesized voice using Vocaloid 2 (and special techniques to tune the parameters).

VocaListener received a lot of coverage in Japan and some of it has been translated to English, for example: here, here, and here.